U.S. patent application number 09/130677 was filed with the patent office on 2001-07-05 for sustained release animal repellents.
Invention is credited to BROWN, LARRY R..
Application Number | 20010006668 09/130677 |
Document ID | / |
Family ID | 26733721 |
Filed Date | 2001-07-05 |
United States Patent
Application |
20010006668 |
Kind Code |
A1 |
BROWN, LARRY R. |
July 5, 2001 |
SUSTAINED RELEASE ANIMAL REPELLENTS
Abstract
Compositions and methods for repelling an animal from an area or
object are described. The compositions include an animal repellent
dissolved or dispersed in a polymer where the repellent is released
from the polymer over a period of time in an amount effective to
repel an animal from the area. Capture of the repellent in the
polymeric matrix allows for concentration of the repellent in an
easily movable or removable device. Moreover, the repellent is not
diluted by contact with water. The composition is provided in a
usable form as a film, a sheet, a shaped article, pellets, or
microparticles. The method for repelling an animal from an area or
object includes preparing a device incorporating the above
compositions and placing the device in an area or near or on an
object desired to be protected. The devices can be manufactured by
solvent evaporation, solvent removal, coextrusion, spray drying,
and hot melt encapsulation. In a preferred embodiment the polymer
is ethylene vinyl acetate copolymer and the repellent is methyl
nonyl ketone or animal predator urine.
Inventors: |
BROWN, LARRY R.; (NEWTON,
MA) |
Correspondence
Address: |
PATREA L PABST
ARNALL GOLDEN & GREGORY LLP
2800 ONE ATLANTIC CENTER
1201 W PEACHTREE STREET
ATLANTA
GA
303093450
|
Family ID: |
26733721 |
Appl. No.: |
09/130677 |
Filed: |
August 6, 1998 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60054994 |
Aug 6, 1997 |
|
|
|
Current U.S.
Class: |
424/405 ;
424/409; 424/411; 514/675; 523/122 |
Current CPC
Class: |
Y10S 514/92 20130101;
A01N 25/18 20130101; A01N 35/02 20130101; A01N 63/10 20200101; A01N
63/10 20200101; A01N 25/18 20130101; A01N 25/10 20130101; A01N
35/02 20130101; A01N 25/18 20130101; A01N 25/10 20130101; A01N
35/02 20130101; A01N 2300/00 20130101; A01N 63/10 20200101; A01N
2300/00 20130101; A01N 63/10 20200101; A01N 63/50 20200101; A01N
25/18 20130101; A01N 25/10 20130101; A01N 63/10 20200101; A01N
63/50 20200101; A01N 2300/00 20130101 |
Class at
Publication: |
424/405 ;
424/408; 424/409; 424/411; 514/675; 523/122 |
International
Class: |
A01N 025/00; A01N
025/34; A01N 025/08 |
Claims
What is claimed is:
1. A composition for repelling an animal from an area or object,
comprising: a polymer; a repellent dispersed in the polymer;
wherein the repellent is released from the polymer over a period of
time in an amount effective to repel an animal from the area or
object.
2. The composition of claim 1 wherein the polymer is selected from
the group consisting of ethylene vinyl acetate copolymer,
polyethylene, polypropylene, poly(vinyl chloride), polyesters,
polyorthoesters, polysaccharides, poly(urethanes),
poly(anhydrides), poly(carbonates), poly(acrylates),
poly(butadienes), fluoropolymers, poly(acryonitriles), poly(vinyl
acetate), poly(methyl methacrylate), poly(styrene),
poly(oxymethylene), poly(oxyethylene-oxyterephthaloyl),
poly(ethylene terephthalate), poly(amides), polyamino acids, and
copolymers and mixtures thereof.
3. The composition of claim 1 wherein the polymer is ethylene vinyl
acetate copolymer.
4. The composition of claim 2 wherein the polyester is polylactide,
polyglycolide, or a copolymer or mixture thereof.
5. The composition of claim 2 wherein the polysaccharide is
dextran, cellulose, dextran sulfate, or food starch.
6. The composition of claim 2 wherein the polyamino acid is
polylysine or polyarginine.
7. The composition of claim 1 wherein the repellent is selected
from the group consisting of methyl nonyl ketone and animal
predator urine.
8. The composition of claim 1 wherein the repellent is methyl nonyl
ketone.
9. The composition of claim 1 wherein the repellent is animal
predator urine.
10. The composition of claim 1 wherein the composition is in a form
selected from the group consisting of a film, a sheet, a shaped
article, pellets, and microparticles.
11. A method for repelling an animal from an area or object
comprising: providing a repellent composition comprising a
repellent contained in a polymer, wherein the composition releases
the repellent over a period of time; and exposing the animal to the
repellent composition.
12. The method of claim 11 wherein the repellent is selected from
the group consisting of methyl nonyl ketone and animal predator
urine.
13. The method of claim 11 wherein the polymer is selected from the
group consisting of ethylene vinyl acetate copolymer, polyethylene,
polypropylene, poly(vinyl chloride), polyesters, polyorthoesters,
polysaccharides, poly(urethanes), poly(anhydrides),
poly(carbonates), poly(acrylates), poly(butadienes),
fluoropolymers, poly(acryonitriles), poly(vinyl acetate),
poly(methyl methacrylate), poly(styrene), poly(oxymethylene),
poly(oxyethylene-oxyterephthaloyl), poly(ethylene terephthalate),
poly(amides), polyamino acids, and copolymers and mixtures
thereof.
14. The method of claim 12 wherein the polymer is ethylene vinyl
acetate copolymer.
15. A method for manufacture of an animal repellent composition
comprising: dissolving a polymer in a solvent; dispersing a
repellent in the polymer solution; and removing the solvent from
the solution.
16. The method of claim 15 wherein the repellent is selected from
the group consisting of methyl nonyl ketone and animal predator
urine.
17. The method of claim 15 wherein the polymer is selected from the
group consisting of ethylene vinyl acetate copolymer, polyethylene,
polypropylene, poly(vinyl chloride), polyesters, polyorthoesters,
polysaccharides, poly(urethanes), poly(anhydrides),
poly(carbonates), poly(acrylates), poly(butadienes),
fluoropolymers, poly(acryonitriles), poly(vinyl acetate),
poly(methyl methacrylate), poly(styrene), poly(oxymethylene),
poly(oxyethylene-oxyterephthaloyl), poly(ethylene terephthalate),
poly(amides), polyamino acids, and copolymers and mixtures
thereof.
18. The method of claim 15 wherein the polymer is ethylene vinyl
acetate copolymer.
19. Animal repellent devices comprising: the composition of claim 1
formed into a shaped article, a film, a sheet, pellets, or
microparticles.
20. The device of claim 19 wherein the polymer is ethylene vinyl
acetate copolymer and the repellent is selected from the group
consisting of methyl nonyl ketone and animal predator urine.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to provisional
patent application Serial No. 60/054,994, filed on Aug. 6,
1997.
FIELD OF THE INVENTION
[0002] The present invention is in the field of methods and
compositions for repelling animals.
BACKGROUND OF THE INVENTION
[0003] For many reasons, including health and safety related
reasons, people often desire to repel animals from a particular
area or object. For example, in urban, suburban, and rural regions
frequented by wild animals, such as raccoons, squirrels, etc., it
is often a problem that the animals will disrupt garbage cans and
other refuse receptacles, leading to refuse strewn over the ground.
This problem is also commonly faced in areas where domesticated
animals are allowed to roam unattended. It is also often desired to
repel domesticated animals such as dogs and cats from household
areas or objects such as a couch.
[0004] Methyl nonyl ketone is presently used as a dog and cat
repellent/training aid and as an iris borer deterrent in
residential households and dwellings, on outdoor paths and patios,
in solid waste containers, with ornamental and shade trees,
ornamental herbaceous plants, ornamental lawns, and with ornamental
woody shrubs and vines such as around perimeters of vegetable
plantings. U.S. Pat. No. 4,775,532 discloses a liquid composition
of methyl nonyl ketone and di(alkyl)adipate for use in repelling
and training dogs and cats.
[0005] Methyl nonyl ketone is generally formulated as a pressurized
liquid, as a ready-to-use liquid in a pump/sprayer device, or as a
solid granular or crystalline formulation. The liquid formulations
contain about 1.9% methyl nonyl ketone and about 0.1% related
compounds. Various solid formulations are available as 1.9% methyl
nonyl ketone and 0.1% related compounds, 0.08% methyl nonyl ketone
and 0.42% cinnamaldehyde, or 6.25% thiram, 6.25% methyl nonyl
ketone and 5.50% castor oil.
[0006] Methods of application of the preparations presently used
include spreading the granular or crystalline formulation onto soil
or ground as a border treatment, between rows of plants, or around
the base of ornamental plants and objects. The pressurized liquid
or liquid ready-to-use formulations are applied to the bark of
trees and base of shrubs. For surface and indoor treatments, a
piece of cloth can be sprayed and attached to the item to be
protected.
[0007] The pressurized liquid or ready-to-use liquid products
reportedly repels cats and dogs for about 12 to 14 hours following
application. Repeat application is recommended after rain.
[0008] Many users claim that the presently available formulations
of methyl nonyl ketone do not function effectively to repel
animals. Short duration of repellency and low concentration of
repellent in the vicinity of the item or area to be protected are
reasons cited for ineffectiveness.
[0009] The application of methyl nonyl ketone upon surfaces and
objects presents many problems. The chemical cannot be applied
directly to ornamental or other plants because vegetation may be
damaged. The use of methyl nonyl ketone in commercial food
processing or preparation areas is not recommended nor is the
application of methyl nonyl ketone to food crops or to soft stemmed
bodied plants or application directly to water. Pressurized liquid
and liquid ready-to-use formulations may stain or soften some
fabrics or plastics.
[0010] It is therefore an object of the present invention to
provide a self contained composition which provides controlled
release of animal repellent over a period of time.
BRIEF SUMMARY OF THE INVENTION
[0011] Compositions and methods for repelling an animal from an
area or object are described. The compositions include an animal
repellent dissolved or dispersed in a polymer where the repellent
is released from the polymer over a period of time in an amount
effective to repel an animal from the area. Capture of the
repellent in the polymeric matrix allows for concentration of the
repellent in an easily movable or removable device. Moreover, the
repellent is not diluted by contact with water.
[0012] In a preferred embodiment the polymer is ethylene vinyl
acetate copolymer and the repellent is methyl nonyl ketone or
animal predator urine. The composition is provided as a film, a
sheet, a shaped article, pellets, or microparticles.
[0013] The method for repelling an animal from an area or object
includes preparing a device incorporating a composition as
described above and placing the device in an area or near or on an
object desired to be protected. The devices can be manufactured by
various methods such as solvent evaporation, solvent removal,
diffusion into preformed matrices, coextrusion, spray drying, and
hot melt encapsulation.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1 illustrates sustained release of methyl nonyl ketone
from EVAc copolymer matrices as a function of weight percent
loading, where .quadrature. indicates 20% loading (w/w),
.box-solid. indicates 31% loading (w/w), .largecircle. indicates
49% loading (w/w), .circle-solid. indicates control of no polymer,
and .DELTA. indicates control of no polymer and no solvent.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Controlled release formulations in polymeric vehicles have
been used for delivery of pesticides, insecticides, fertilizer,
detergents, perfumes and in drug delivery. U.S. Pat. No. 5,017,377
to Sikinama et al. discloses a controlled release insect pest
repellent including p-menthane-3,8-diol blended with an ethylene
vinyl acetate copolymer.
[0016] Controlled release formulations can be formulated using
either non-degradable or degradable polymeric materials. In one
type of polymeric delivery system, a polymeric capsule is formed
around or incorporating the agent to be delivered. The type of
agent being delivered and the environment in which the agent is
intended to be used determine the composition of the polymer or
polymers used and the method that can be used to incorporate the
agent. Alternatively, the polymer can be in the form of a sheet,
pellets, a film, or a shaped article.
[0017] Unlike the uncontrolled application of repellents such as
methyl nonyl ketone in the presently marketed forms, in the present
device and method the repellent is released from the polymeric
compositions in a controlled manner for a longer time period and at
a sustained effective repellent concentration. Controlled release
devices are disclosed which can be placed and/or affixed where
desired, moved around, and removed when desired. Continuous release
of repellent is provided over a several week time period and the
repellent is protected from environmental elements such as rain
without the need for reapplication. In addition, the device can be
fabricated so that release only occurs from a single surface of the
device, allowing it to be placed on or adjacent to ornamental
plants and/or vegetation without damaging the plant.
[0018] In one embodiment, the composition is a polymeric film that
incorporates methyl nonyl ketone therewithin. In another
embodiment, the composition is a polymeric film containing an
environmentally inert and safe repellent such as predator's
urine.
[0019] A. Compositions
[0020] The compositions are made from a polymer and an animal
repellent. The compositions may be manufactured as devices such as
shaped articles, films, sheets, pellets, or microparticles.
[0021] Repellents
[0022] Methyl nonyl ketone, also known as 2-undecanone, and related
chemicals known to act to repel animals can be used. Alternatively,
or in addition, other repellents can be used such as those
contained in the urine of various predators to the animals one
wants to repel. For example, fox urine can be used, as foxes are
known predators to squirrels, rabbits, deer, woodchucks, raccoons,
chipmunks and other varmints. Coyote urine and bobcat urine can be
used, as coyotes and bobcats are known predators to mice, moles and
deer. Wolf urine can also be used, as wolves are predators to
moose, coyote and bears. These repellents can be used as urine or
as an isolated or synthesized form of chemicals contained in the
urine and can be used in lyophilized form.
[0023] Other repellents include N,N-diethyltoluamide (DEET),
cinnamaldehyde, thiram, capsicum, and quinine. The method and
materials described herein are not limited to any particular
repellent but are applicable to any which can be incorporated into
a sustained release matrix as described herein. Preferred compounds
are hydrophilic, lipophilic, or particulate in form, such as
aliphatic or aromatic compounds possessing repellent
properties.
[0024] Polymers
[0025] A number of polymers can be used. The polymer must be
compatible with the repellent and able to release the repellent
over time, such as by degradation of the polymer. The polymer
itself should not have detrimental effects on the area or object
with which it is to be used, such as foliage if the composition is
to be applied directly to plants. Preferably, the polymer is not
water soluble or is only marginally water soluble and there is
minimal leeching of the repellent out of the composition upon
contact with water.
[0026] A preferred polymer is ethylene vinyl acetate (EVAc) because
it is compatible with aliphatic and aromatic compounds such as
methyl nonyl ketone. EVAc yields a homogenous, flexible film which
is compliant and can possess adhesive qualities. EVAc is
hydrophobic which protects the incorporated repellent from
leaching. Examples of other polymers and classes of polymers which
can be used include poly(ethylene), poly(propylene), polyvinyl
polymers such as poly(vinyl chloride), polyesters such as
polylactide and polyglycolide and copolymers and mixtures thereof,
poly orthoesters, polysaccharides such as dextran, dextran sulfate,
cellulose, starches, acid hydrolyzed hydroxypropyl ether starches,
polyurethanes, poly(anhydrides), poly(carbonates), poly(acrylates),
poly(butadienes), fluoropolymers, poly(acryonitriles), poly(vinyl
acetate), poly(methyl methacrylate), poly(styrene),
poly(oxymethylene), poly(oxyethylene-oxyterephthaloyl),
poly(ethylene terephthalate), poly(amides), polymers containing
cyclic groups and aromatic polymers, and polyamino acids such as
polylysine and polyarginine.
[0027] B. Methods for making the compositions
[0028] The concentration of repellent in the matrix can range from
10% to 90% by weight, preferably between 20% and 80%, most
preferably between about 30% and 70%.
[0029] The polymeric compositions incorporating the repellent can
be produced by a number of techniques, depending upon the polymer
and the nature of the desired composition. For shaped articles,
pellets, films and sheets, preferred methods are solvent
evaporation and coextrusion of the repellent and polymer. Particles
can be produced using solvent evaporation, spray drying, solvent
removal, and hot melt encapsulation, as discussed below.
[0030] Shaped Articles, Pellets. Films and Sheets
[0031] Solvent Evaporation. In this method the polymer is dissolved
in a volatile organic solvent such as methylene chloride. The
repellent is added to the polymer solution and the combination is
mixed. The mixture is poured into a mold or other receptacle having
the desired shape and size, and the solvent is evaporated from the
mixture.
[0032] Co-Extrusion. In this method, the polymer is granulated and
melted. The repellent is added and mixed with the polymer and the
combination is extruded through an injection molder such as a twin
screw extrusion device. A plasticizer such as
di(n-butyl)-o-phthalate, di(n-dodecyl)-o-phthalate,
di(n-ethyl)-o-phthalate, di(n-heptyl)-o-phthalate,
di(n-methyl)-o-phthalate, di(n-nonyl)-o-phthalate,
di(n-propyl)-o-phthalate, or tricresyl phosphate can be added to
lower the melting point of the polymer, allowing it to be extruded
at a lower temperature. An important advantage of co-extrusion is
that an organic solvent is not required.
[0033] Particles
[0034] Solvent Evaporation. In this method the polymer is dissolved
in a volatile organic solvent such as methylene chloride. The
repellent is added to the polymer solution and the combination is
mixed. The mixture is sonicated or homogenized and the resulting
dispersion or emulsion is added to an aqueous solution that
contains a surface active agent such as TWEEN.TM. 20, TWEEN.TM. 80,
PEG or poly(vinyl alcohol) and homogenized to form an emulsion. The
resulting emulsion is stirred until most of the organic solvent
evaporates, leaving microparticles. Several different polymer
concentrations can be used between about 0.05 to 0.60 g/ml.
Microparticles with different sizes, from about 1 to 1000 microns,
and morphologies can be obtained by this method. This method is
useful for relatively stable polymers like polyesters.
[0035] Solvent evaporation is described by E. Mathiowitz, et al.,
J. Scanning Microscopy, 4, 329 (1990); L. R. Beck, et al., Fertil.
Steril., 31, 545 (1979); and S. Benita, et al., J. Pharm. Sci., 73,
1721 (1984), the teachings of which are incorporated herein.
[0036] Labile polymers, such as polyanhydrides, may degrade during
this fabrication process due to the presence of water. For these
polymers, the following two methods, which are performed in
completely organic solvents, are more useful.
[0037] Hot Melt Microencapsulation. In this method, the polymer is
first melted and then mixed with the repellent. The mixture is
suspended in a non-miscible solvent (like silicon oil), and, while
stirring continuously, heated to 5.degree. C. above the melting
point of the polymer. Once the emulsion is stabilized, it is cooled
until the polymer particles solidify. The resulting microparticles
are washed by decantation with a polymer non-solvent such as
petroleum ether to give a free-flowing powder. Microparticles with
sizes between one to 1000 microns can be obtained with this method.
The external surfaces of particles prepared with this technique are
usually smooth and dense. This procedure is used to prepare
microparticles made of polyesters and polyanhydrides. However, this
method is limited to polymers with molecular weights between about
1000 to 50,000.
[0038] Hot-melt microencapsulation is described by E. Mathiowitz,
et al., Reactive Polymers, 6, 275 (1987), the teachings of which
are incorporated herein. Polyanhydrides, for example, made of
bis-carboxyphenoxypropane and sebacic acid with molar ratio of
20:80 (P(CPP-SA) 20:80) (Mw 20,000), can be prepared by hot-melt
microencapsulation or for example, poly(fumaric-co-sebacic) (20:80)
(Mw 15,000) microparticles can be prepared by hot-melt
microencapsulation.
[0039] Solvent Removal. This technique was primarily designed for
polyanhydrides. In this method, the repellent is dispersed or
dissolved in a solution of the selected polymer in a volatile
organic solvent like methylene chloride. This mixture is suspended
by stirring in an organic oil (such as silicon oil) to form an
emulsion. Unlike solvent evaporation, this method can be used to
make microparticles from polymers with high melting points and
different molecular weights. The external morphology of particles
produced with this technique is highly dependent on the type of
polymer used.
[0040] Spray Drying of Microparticles. Microparticles can be
produced by spray drying by dissolving a biocompatible polymer in
an appropriate solvent, dispersing the repellent into the polymer
solution, and then spray drying the polymer solution, to form
microparticles. As defined herein, the process of "spray drying" a
solution of a polymer and a repellent refers to a process wherein
the solution is atomized to form a fine mist and dried by direct
contact with hot carrier gases. Using spray drying apparatus
available in the art, the polymer solution may be delivered through
the inlet port of the spray drier, passed through a tube within the
drier and then atomized through the outlet port. The temperature
may be varied depending on the gas or polymer used. The temperature
of the inlet and outlet ports can be controlled to produce the
desired products.
[0041] The size of the particulates of polymer solution is a
function of the nozzle used to spray the polymer solution, nozzle
pressure, the flow rate, the polymer used, the polymer
concentration, the type of solvent and the temperature of spraying
(both inlet and outlet temperature) and the molecular weight.
Generally, the higher the molecular weight, the larger the particle
size, assuming the concentration is the same. Typical process
parameters for spray drying are as follows: polymer
concentration=0.005-0.20 g/ml, inlet temperature=30-1000.degree.
C., outlet temperature=20-100.degree. C., polymer flow rate=5-200
ml/min., and nozzle diameter=0.2-4 mm ID. Microparticles ranging in
diameter between one and ten microns can be obtained with a
morphology which depends on the selection of polymer,
concentration, molecular weight and spray flow.
[0042] Hydrogel Microparticles. Microparticles made of gel-type
polymers, such as polyphosphazene or polymethylmethacrylate, are
produced by dissolving the polymer in an aqueous solution, if
desired suspending a repellent in the mixture, homogenizing the
mixture, and extruding the material through a microdroplet forming
device, producing microdroplets which fall into a hardening bath
consisting of an oppositely charged ion or polyelectrolyte
solution, that is slowly stirred. The advantage of this technique
is the ability to further modify the surface of the microparticles
by coating them with polycationic polymers, such as polylysine,
after fabrication. Microparticle sizes are controlled by using
various size extruders.
[0043] Solvents
[0044] As defined herein, the polymer solvent is an organic solvent
that is volatile or has a relatively low boiling point or can be
removed under vacuum, such as dichloromethane (methylene chloride).
Other solvents, such as ethyl acetate, ethanol, methanol, dimethyl
formamide (DMF), acetone, acetonitrile, tetrahydrofuran (THF),
acetic acid, dimethyl sulfoxide (DMSO) and chloroform also may be
utilized, or combinations thereof. In general the polymer is
dissolved in the solvent to form a polymer solution. When EVAc is
the polymer, for example, the repellent can be at a concentration
of between about 5% and 40% weight to volume (w/v), more preferably
between about 10% and 20% w/v.
[0045] C. Methods for using the devices
[0046] The devices are placed in desired locations such as on the
side, top, or inside a garbage can, around the base of a tree, or
on top of or under a piece of furniture. The devices can also be
directly attached to an object or area to be protected.
[0047] When the compositions are formulated as microspheres they
can be widely distributed across an area to be protected by using a
spreader, for example. Other means of dispersion can also be used
as well as direct application by shaking or pouring the particles
onto the desired area.
EXAMPLES
[0048] The compositions and methods described herein will be better
understood with reference to the following non-limiting
examples.
[0049] Materials
[0050] Ethylene vinyl acetate copolymer was obtained from USI
Vynathene Quantum Chemicals under the tradename USI VYNATHENE.TM..
Methyl nonyl ketone was obtained from Acros Chemicals. Coyote and
bobcat urine were obtained from Foggy Mountain, DG-100, J&C MK,
Hampden, Me. L101 Pluronic was obtained from BASF Corporation,
Parsipanny, N.J. Pure Cote B790 food starch was obtained from Grain
Processing Corporation, Muscatine Iowa.
Example 1
Polymeric Sheet Containing Methyl Nonyl Ketone
[0051] Ten (10) grams of ethylene vinyl acetate copolymer (EVAc),
40% vinyl acetate by weight, was dissolved in a total volume of 100
ml dichloromethane. The copolymer was allowed to dissolve over a 16
hour period in order to create a 10% (wt/vol.) solution of the
polymer in dichloromethane. Ten (10) grams of methyl nonyl ketone
was added to the polymer solution and the mixture was shaken to
form a slightly yellowish, homogeneous solution. A polypropylene
plastic dish was used as a casting mold for the repellent/polymer
solution. The solution was poured into the mold/dish forming a flat
sheet on the bottom of the mold. The dichloromethane was allowed to
evaporate overnight and the final composition formed a dry film on
the bottom of the mold that contained about 50% by weight methyl
nonyl ketone.
[0052] Seven days after the fabrication of a controlled release
device described above, the device was partially filled with bird
seed which contained sunflower seeds in their shells. A control
dish containing no repellent was also partially filled with
sunflower seeds. The containers were attached to wooden boards and
placed ten feet apart in an area which had been observed to attract
significant numbers of squirrels, raccoons and birds. The
temperature during the 24 hour test period ranged from 39.degree.
F. to 60.degree. F., with no precipitation and about 40% humidity.
The test period was sunny for most of the daylight hours.
[0053] After 24 hours, the contents of the control container showed
signs of animal use. Most nut-type sunflower seeds were gone. Seed
husks were littered on the ground adjacent to the control
container. The wooden board had been moved from its original
position. In contrast, the repellent device showed no signs of
having been touched by animals. Nut-type sunflower seeds were still
in the device and no husks were around the device. The wooden board
remained in its original position. Thus, the device described above
repelled animals up to at least seven (7) days after
fabrication.
Example 2
Evaluation of Release of Repellent as a Function of Percent
Loading
[0054] Repellent devices were fabricated with varying quantities of
an active repellent, methyl nonyl ketone, in order to demonstrate
the sustained release of the repellent over a 68 day period. The
devices were fabricated as described in Example 1, with varying
quantities of methyl nonyl ketone as outlined in Table I. The
solutions were cast into 5 cm diameter polypropylene caps and
allowed to dry overnight.
1TABLE I Fabrication variables of methyl nonyl ketone test films
and controls. 10% (wt/wt) methyl nonyl methyl nonyl EVAc/ ketone
ketone CH.sub.2Cl.sub.2 (wt % w. CH.sub.2Cl.sub.2 (grams) (grams)
EVAc) (grams) 0.510 20.69 20 0 1.000 22.53 31 0 2.001 20.84 49 0
2.010 0 100 19.44 2.000 10 100 0
[0055] The release of the methyl nonyl ketone was determined by
measuring the decrease in weight of the films using an analytical
balance (Mettler-Toledo model 302) over 68 days. The release
kinetics are graphed in FIG. 1 as the cumulative mg of methyl nonyl
ketone released over the time period.
[0056] The data demonstrates the sustained release of the repellent
over a 68 day time period and the ability to control the amount
released over time by varying the loading of the EVAc matrices.
Increasing the weight percent loading of the methyl nonyl ketone in
the matrix resulted in larger quantities of nonyl methyl ketone
released. The control devices (the last two entries in the table)
demonstrate that the addition of CH.sub.2Cl.sub.2 to methyl nonyl
ketone exhibited no effect on release as compared to the control
containing no CH.sub.2Cl.sub.2.
[0057] The device therefore continuously releases the repellent
while protecting dilution of the repellent due to environmental
forces such as rain, snow, wind and runoff. The device also allows
the concentration of effective quantities of methyl nonyl ketone in
safe and easy to handle polymeric devices for use in the continuous
repelling of nuisance animals.
Example 3
Use of Devices to Repel Other Animals
[0058] Repellent delivery devices prepared as in Example 1 above
were prepared and attached to a garbage bag filled with decomposing
food stuffs including fruit rinds, proteins and vegetables. The bag
was left out overnight in an area known to be frequented by
raccoons and other animals. After 2 days in an unprotected
environment, the bag remained intact. It did contain some holes,
presumably introduced by animals which tried to enter the bag but
which were repelled by the continuous delivery of methyl nonyl
ketone from the delivery devices.
[0059] Animal repellent devices prepared as described in Example 1
were placed in a vegetable garden containing several tomato plants
that was regularly violated by squirrels and other small animals.
The small animals ceased from disturbing the vegetable garden for
several weeks.
[0060] Animal repellent devices prepared as described in Example 1
were placed on a house deck known to be frequented by raccoons,
attached with a string to the outside of a 30 gallon garbage
container. The garbage container remained outside for two weeks and
overturning and disruption of the garbage container ceased. After
the two week test period, the repellent devices were removed and
the garbage container not protected by the repellent devices was
found overturned and garbage was strewn about the surrounding area
on the morning following the removal of the repellent device.
[0061] These results indicate that these devices effectively
protect an area in a safe and effective manner over an extended
time period.
Example 4
Device Containing Animal Predator Urine
[0062] 4.53 grams of coyote urine was combined with 0.63 grams of
L101 Pluronic. 50 grams of 10% EVAc dissolved in dichloromethane
(wt/vol) was then mixed with the coyote urine and L101 Pluronic
solution. The mixture was vigorously shaken, forming a dispersion
of the coyote urine within the polymer solution. The dispersion was
then cast into a 6 inch by 8 inch aluminum pan and allowed to dry
into a film overnight.
[0063] The aluminum backed film was cut into strips approximately
1.5 inches wide by 6 inches long. The film strips were affixed to
various points in the front and back yard of a home being
frequented by skunks and raccoons. The strips remained on the
property over a 2 month period.
[0064] The raccoons ceased to disrupt the garbage cans of the home
for the first time in several months over the two month test
period. The skunks also ceased to release their offensive odors in
and around the home.
[0065] These results indicate that the sustained release of the
coyote urine from these polymer matrices controlled and prevented
raccoons and skunks from frequenting this household and its
surroundings.
Example 5
Device Containing Animal Predator Urine
[0066] 10 grams of coyote urine was dispersed in 100 ml of a 10%
(wt/vol.) solution of ethylene vinyl acetate copolymer dissolved in
dichloromethane. The solution was shaken vigorously and then cast
into molds. The molds were precooled to insure homogeneous
distribution of the aqueous urine solutions. In a alternate
embodiment of the device, the predator urine can be dried by
methods such as freeze drying to remove the water contained in
urine. The remaining solid material can be incorporated into the
device by dispersing the dried urine material in a 10% (wt/vol.)
solution of ethylene vinyl acetate copolymer dissolved in
dichloromethane. The suspension can then be cast into molds. Both
methods will yield a thin polymer film, which is placed in areas
where animals such as squirrels, mice, deer etc. are
troublesome.
Example 6
Aqueous Based Modified Food Starch Film Containing Bobcat or Coyote
Predator Urine
[0067] It may be desirable in some cases to incorporate water
soluble repellents into aqueous based polymer films. In order to
accomplish this, 75.3 grams of pure Cote B790 modified food starch
was dispersed in 150 ml cold water. The suspension was heated to
82.degree. C. and held at that temperature for 12 minutes. The
suspension turned to a translucent solution, which is a hydrated
starch slurry. 50 ml of the slurry was cast into a plastic mold
containing 10 ml of bobcat or coyote urine and allowed to dry
overnight. The resulting dried composition could be used as a
repellent device.
[0068] The teachings of the references cited herein are
specifically incorporated herein. Modifications and variations of
the present invention will be obvious to those skilled in the art
from the foregoing detailed description and are intended to be
encompassed by the following claims.
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